At the start of this summer, France implemented a ban on short‑haul flights for routes under 2.5 hours, nudging travelers toward rail. France becomes the first country to adopt this measure to curb greenhouse gas emissions. Adeline de Montlaur, an aeronautical engineer and professor at the Universitat Politècnica de Catalunya, and her colleagues published a 2021 study on the CO2 impact of short flights. The takeaway is clear: shorter flights tend to pollute more per passenger than longer ones.
-To what extent do short flights under roughly 500 kilometers pollute?
-Answer: it depends on the lens. When viewed as a share of total flights, the impact is small. When assessing pollution per passenger per kilometer, short flights are more harmful than long ones. The Eurocontrol data, representing industry norms, shows about 3.4 liters per passenger per 100 km on average, but this drops or rises with flight length. On shorter hops this figure can easily double, reaching around 6 liters per passenger for some short trips. Variability comes from aircraft type and other factors.
-Why does the disparity occur?
-Takeoff and landing make up a large portion of the energy used. Climbing to cruising speed requires more thrust, and fuel burn is highest during takeoff. While all flights have a departure, shorter flights incur a higher relative fuel cost because they spend less time in the efficient cruise phase. In short, the overhead of getting in the air is a bigger share of the journey for short flights, making the total per‑trip emissions higher compared with longer flights.
“Proportionally, the takeoff of a short flight consumes more fuel than the takeoff of a long flight.”
Another focus of the study is the ground taxiing and runway movements. Ground handling accounts for a noticeable share of emissions. Eurocontrol data from 2022 shows about 15% of total flight time in Europe is spent taxiing, while fuel is burned during this push along the runway. At major European hubs, taxi times can add 20–30 minutes to total flight time. For a one‑hour flight, the taxi portion represents a larger share of emissions than it would on longer trips to destinations such as the United States.
-Does this pattern hold for all aircraft?
-The trend shows ongoing modernization. Aircraft are becoming more efficient, and efficiency has improved over the last two decades. Yet overall fuel burn and emissions rise because air traffic volume grows faster than efficiency gains. Technology alone has not kept emissions in check.
-Can the French ban really cut emissions? Some industry voices doubt it.
-The discussion began with a citizens’ forum of about 150 people proposing that flights with train alternatives be banned for a maximum of 4 hours round trip, later set at 2.5 hours. The measure currently affects only Paris Orly to Nantes, Bordeaux, and Lyon routes. Connecting flights are exempt, but many routes were already culled during the Covid period due to low demand. The European Union welcomed the move and suggested extending similar logic to other large hubs such as Charles de Gaulle to ensure continuity with connecting services. The key question remains: will the policy broaden and adapt to more routes and better train connectivity for international travelers?
“The France policy is beneficial but should cover more flights, including connections.”
It is more about door‑to‑door time than comparing the clocked flight duration. For travelers starting from homes to final destinations, train and plane times can be similar or even faster when well connected. This kind of comparison matters for travelers in North America too, where train and high‑speed rail networks are expanding in parts of the US and Canada, affecting choices for cities linked by efficient rail connections.
– Are airfares on rail routes competitive?
-Ticket economics matter. Short trips inside regions like Barcelona–Madrid can tilt toward rail, but historically air travel has benefited from fuel subsidies. Aviation fuels carry different taxes than road fuels, creating pricing distortions. In an era of climate urgency, tax policy and greener fuels matter for rail and air alike. This is not a purely national issue; Europe moves first, with implications for North America as well.
-Is the aviation sector headed toward zero emissions by 2050?
-Forecasts vary. The industry speaks of a mix: partial efficiency gains, some electric or hybrid options for shorter legs, and broader use of sustainable aviation fuels (SAF). Yet critics argue that SAF costs are high and scaling remains uncertain. If SAF prices stay elevated, ticket prices could rise and the path to net zero remains challenging. Emissions offsets like tree planting are part of the plan, but the economics of SAF are a major hurdle.
“The goal of net zero emissions by 2050 for aviation is questionable.”
Analysts note that the price of SAF can be several times higher than conventional fuel, and prices may not fall quickly. If industry promises are realized, travelers would feel the impact in ticket prices. That is a reality many countries, including North America, are watching closely as policymakers weigh incentives and infrastructure for greener aviation. The debate continues about how to balance progress with affordability and access.
-Could a French model work in Spain and beyond?
-Political will is crucial. Airlines alone cannot drive change. A broader European approach might be more effective, and extending the 2.5–hour window for rail alternatives could have larger, longer‑term effects. In North America, where rail networks are more developed in parts of the continent, similar policy discussions could shape cross‑country travel and emissions trajectories.
Reference work: MDPI sustainability study on transport and emissions patterns, 2021. (Attribution: MDPI Sustainability, 2021)
– This summary reflects ongoing research and debate about transport emissions, policy choices, and the role of rail as an alternative to short-haul flights in North America as well as Europe.